Medical advances mean that many us aren't just made up of bone and flesh these days: artificial knees, titanium plates and pacemakers make their way into human bodies across the world every day. But what happens to them when their owners are cremated?

A report by the BBC offers some reassuring news. Fortunately, all the metal doesn't go to waste. In fact, there's a booming business in recycling the implants that get left behind when corpses make their way into the incinerator.

Ruud Verberne, co-founder of implant recyclers OrthoMetals, explains to the BBC that his company deals with everything, from titanium hips to cobalt-chrome knees.

Before Verberne set up his Dutch company—which has since inspired five or six new companies to start up in the US—the implants used to be buried. Now, they're collected from the crematorium, sorted, and melted down. No, don't be silly: of course they're not reused. In total, Verbeme's company deals with 250 tons of metal from cremations every year, much of which makes its way into cars, planes and even wind turbines.

It's hardly a lucrative business though: a single hip replacement unit is worth about $3. So, better not bank on your grandmother's titanium implants forming part of your inheritance. [BBC]